Employing Poly(4‐Vinylpyridine) as the Dielectrics for Enhanced Molybdenum Disulfide Field‐Effect Transistors

Herein, field‐effect transistors (FET) based on multilayer molybdenum disulfide (MoS₂) nanoflakes are fabricated by employing poly(4‐vinylpyridine) (PVP) as the modified layer of typical inorganic dielectric (SiO₂). The MoS₂ nanoflakes are directly exfoliated from bulk MoS₂ and transferred onto the PVP surface instead of bare SiO₂ substrate that renders the enlarged nanoflake size. Taking advantage of the high surface energy and low surface roughness of PVP surface, the enhanced interaction between PVP and MoS₂ bulk crystal may be achieved that is responsible for the large‐size MoS₂ nanoflakes (≈2.5 × 10⁵ μm²). Importantly, MoS₂ FETs based on the double‐gate insulators consisting of PVP and SiO₂ exhibit improved device performances. The on‐state current presents a fivefold increase and the field‐effect mobility is improved from 4.75 to 167.79 cm² Vs⁻¹, which are attributed to the PVP surface with low charge‐trap states and the lowered Schottky Barrier height (Φ_SB). The current studies will effectively push the applications of MoS₂ nanoflakes in flexible electronics.